Drivetrain Woes!!!**FOUND IT**

[slowtwitch]

Road bike 9 speed shimano 11/21 52/39 and the problem is as follow:

 

my chain skips in the gear, but only on 21T and 20T.

I've checked the chainwear - it's fine

Thought the cassette is done, so I replaced with a 12-23 new one.

It still does the same - skips in the bottom 2 gears.

 

Shifting is smooth, chain runs smooth in the gear and then jumps, runs smooth, then jumps, but only in the bottom 2 gears i.e. 23T and 22T.

 

I've loosened the gear cable checked top and bottom adjusting screws, B tenssion screw, all is fine.

 

I must mention that this only started after I stripped the whole bike and rebuilt it (with same groupo)

 

What did I overlooked????

slowtwitch2009-09-30 23:26:38

[Slowbee]

maybe one of your link pins in the chain is slightly out ?

 

wont explain why it doesnt jump in the other gears though ...

 

[Scooterza]

You didn't misplace a spacer or something in your cluster?  If the other gears are fine, then it is likely something to do with your cluster.  Otherwise you would experience problems in other gears too.  

[droo]

Check your chain for a stiff link and check that there's nothing stuck in the cassette, other than that I'm as lost as you.

[Reghard111]

On both front chairings? Chain might be too long if it does it more on the small blade.

[MoreTrails]

Maybe strip the bike again and the problem will disappear???

 

Buy a mtb and then you can sell your problem...

 

* hat coat door - SLAM*

 

[slowtwitch]

Remember it did with both cassettes. 9speed Tiagra dont have a spacer behind the cassette.

 

I thought maybe stiff link in the chain, but can't feel anything by running the chain through my fingers.

 

I don't think I removed the chain when cleaning the bike (causing stiff link when installing again) and the chain is still same lenght

 

Drivetrain I always keep clean.

 

Must admit didn't check for both chainrings 'cause it's at the bottom 2 gears.

 

When the bike is in a stand there's no issue, only on the road i.e a bit of pressure on the gears - not even climbs

[erikt123]

Hi,

have you checked that your hanger is not bent, if this is the case, and I have many many when the bike has fallen over or when leant on, the hanger has bent and in a lot of cases has only affected the critical gears that you have mentioned. In your top gear i.e. 21 check the alignment of the jockey or take bike to bike shop as their is a special tool for checking frame alingment,

hope this helps

 

regards

|Derek

[slowtwitch]

Shot Derek. Another mech also mentioned this moring that I should double check jockey alignment with the special tool.

 

I've now established that there's no issue in the big blade. so only when I'm in the 39T blade.

 

Must also mention that I had, after the rebuild (and it happend this morning again) in my bottom gear the chain comes off the front blade while spinning in small blade. Previously I found the chainring bolts not completely tight, so I thought it might have been the issue, but obiously not.

 

So there's a serious gremlin in there somewhere.

 

I'll take the bike in 2morow to check jockey alignment, and update this post afterwards

 

 

[Jeepdude]

hallo franna.. ai nog nie uitgesort nie? dit was my volgende raad... is die drop uit nie gebuig nie? wel jy vat hom nou shops toe so die EXperts behoort te kan help... mechanic oor die foon sukkel maar

[droo]

Also check for worn idler pulleys...

[slowtwitch]

No warn pulleys. Drivetrain is the "new" version Tiagra 9speed

 

Mr. van Zyl, ek't obviously jou raad al gevolg sonder sukses.

 

Ek is nie so seker die "x perts" by die bike shop gat die probleem find nie.

 

Ek dink dit het iets te doen met daai voorste small blade, veral noudat hy weer vanoggend met die nonsens begin het om vanself af te kom.

 

O yes and I have removed the crankset and BB again and reinstalled - thinking maybe the cranks were not properly fitted or something

slowtwitch2009-09-17 00:59:41

[Jeepdude]

wel voorspoed. waar is die spring? voor of agter.klim die derailer op en af? die voorste blad sal nie daarmee iets te doen he nie.. maar as die voorste blade probleem gee sal hy in al die ratte pla bertusvanzyl2009-09-17 01:03:46

[slowtwitch]

I found the prob:

I took it to Wayne Phiffer Cycles.

He could not find any problem. The hanger is as strait as a strate stripe (as I expected it to be streight).

So he couldn't find anything. So both of us looked and we looked, and we looked, and we looked...and wolla FOUND IT!!!!!!

 

Could it be, well it was the only thing that we could find, and a 30km ride yesterday confirmed it:

 

My 39T blade was installed wrong way around after I stripped and rebuilt the bike.

 

So when in PE visit Wayne Phiffer Cycles as your pitstop and remember to fit your chainring the correct way, it makes a difference.

[Slowbee]

I found the prob:

I took it to Wayne Phiffer Cycles.

He could not find any problem. The hanger is as strait as a strate stripe (as I expected it to be streight).

So he couldn't find anything. So both of us looked and we looked' date=' and we looked, and we looked...and wolla FOUND IT!!!!!!

 

Could it be, well it was the only thing that we could find, and a 30km ride yesterday confirmed it:

 

My 39T blade was installed wrong way around after I stripped and rebuilt the bike.

 

So when in PE visit Wayne Phiffer Cycles as your pitstop and remember to fit your chainring the correct way, it makes a difference.

[/quote']

 

 

Is your chain installed the correct way as well ?